This disclosure relates to a die stock comprising a substantially cylindrical holder, which is symmetrical to a centric holder longitudinal axis that runs in an axial direction, and has a plurality of receiving grooves each of which is configured for receiving a cutting insert and a clamping wedge, wherein each of the receiving grooves extends from a first end face of the holder in the axial direction, said first end face running transversely to the axial direction, and wherein each of the receiving grooves extends from an inner side of the holder in a radial direction, said inner side facing toward the holder longitudinal axis, wherein a plurality of cutting inserts are provided that are arranged detachably in the receiving grooves, wherein each cutting insert has, on a front side that faces substantially toward the holder longitudinal axis, at least one cutting edge. This disclosure further relates to a holder and a cutting insert for such a die stock.
An exemplary die stock of this generic type is known from WO 2012/117033 A1.
Die stocks, often also referred to as screw dies, are frequently used for machining of external threads and are known in various embodiments. In one embodiment, the die stocks are realized in one piece as a HSS (High Speed Steel) tool. Although these are inexpensive to produce, they are limited in performance and uneconomical due to low cutting data. In addition, if a cutting edge is damaged, the entire die stock has to be exchanged.
Furthermore, die stocks which are made fully of hard metal as a one-piece tool are known. These provide a better performance, but are very expensive and complex in terms of production.
In addition, die stocks having exchangeable cutting inserts are known. These have in principle, however, fewer cutting inserts than the above-stated HSS die stocks and hard metal die stocks, owing to the fitting space conditions. Moreover, because of the necessary space for insertion of the cutting inserts, such die stocks generally provide unfavorable stability of the tool. Examples thereof are known from U.S. Pat. Nos. 2,174,467 A, 2,152,567 A and from GB 406,892 A. In these die stocks, the handling for exchange of the cutting inserts is relatively complex, however. Also the positioning of the individual cutting inserts relative to one another here appears to be quite complex. A further main problem consists in guaranteeing an optimally stable and exactly defined insert fit of the cutting inserts in the die stock holder. In the last-named examples, however, this cannot be assumed.